Device and method for bonding fuel cell part

ABSTRACT

A bonding device of a fuel cell part is disclosed. The bonding device of the fuel cell part may bond an upper gas diffusion layer and a lower gas diffusion layer to top and bottom surfaces of an MEA base material through adhesive layers, while disposing the MEA base material between the upper gas diffusion layer and the lower gas diffusion layer, and may include: a lower die that supports the MEA base material, the upper gas diffusion layer, and the lower gas diffusion layer to be bonded with each other; an upper die installed in an upper side of the lower die; and an ultrasonic wave vibration source that is installed to be capable of moving in a vertical direction at opposite sides of the upper die, compressing the upper gas diffusion layer, and applying ultrasonic wave vibration energy to the adhesive layer.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2019-0044384, filed on Apr. 16, 2019, which isincorporated herein by reference in its entirety.

FIELD

OneThe present disclosure relates to a fuel cell part manufacturingsystem. More particularly, it relates to a bonding device of a fuel cellpart, which bonds a gas diffusion layer (GDL) to opposite sides of amembrane-electrode assembly (MEA), and a method thereof.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may not constitute prior art.

A fuel cell generates electricity by an electrochemical reaction betweenhydrogen and oxygen. The fuel cell can continuously generate electricityby receiving a chemical reactant from the outside without an additionalcharging process.

The fuel cell may be formed by disposing a separator (or a bipolarplate) at opposite sides of a membrane-electrode assembly (MEA). Such afuel cell may be provided in plural and be continuously arranged, andmay be formed by a fuel cell stack.

According to one form, a membrane-electrode assembly, which is a mainpart of the fuel cell, forms an anode electrode layer (catalyst layer)in one side thereof and forms a cathode electrode layer (catalyst layer)in the other side thereof. In addition, each of the opposite sides ofthe MEA is provided with a gas diffusion layer (GDL) that diffuses areaction gas of hydrogen and oxygen to the anode electrode layer and thecathode electrode layer.

A fuel cell part including such a membrane-electrode assembly and a gasdiffusion layer can be manufactured by integrally bonding a gasdiffusion layer to opposite surfaces of a membrane-electrode assembly(hereinafter referred to as an MEA base material).

As a method of bonding the gas diffusion layer to the MEA base material,for example, a hot press method in which the gas diffusion layer appliedwith an adhesive on the edge is disposed on both sides of the MEA basematerial, and the adhesive is heated while compressing the MEA basematerial and the gas diffusion layer with high temperature and highpressure such that the MEA base material and the gas diffusion layer areintegrally bonded to each other, is adopted.

However, in a conventional art, since the edge portion of the gasdiffusion layer, corresponding to a portion where the adhesive isapplied, is compressed with a high pressure (e.g., 1300 kgf), plasticdeformation or damage to an external material (carbonized paper) of thegas diffusion layer can be caused, and accordingly, bonding quality ofthe gas diffusion layer may be deteriorated.

In addition, in the conventional art, heat at a high temperature (forexample, 95° C.) is applied directly to the edge of the gas diffusionlayer, the heat is transferred to the adhesive, and the MEA basematerial and the gas diffusion layer are bonded such that bonding cycletime (for example, 15 seconds) between the MEA base material and the gasdiffusion layer may increase.

In the conventional art, direct application of high temperature heat tothe edge of the gas diffusion layer can cause thermal deformation of theelectrolyte membrane of the MEA base material due to heat applied to theMEA base material.

Furthermore, in the conventional art, consumption of the adhesive may beincreased by bonding the MEA base material and the gas diffusion layerto the edge of the gas diffusion layer at high temperature and highpressure.

The above information disclosed in this Background section is only forenhancement of understanding of the background of the presentdisclosure, and therefore it may contain information that does not formthe prior art that is already known to a person of ordinary skill in theart.

SUMMARY

The present disclosure provides a bonding device of a fuel cell part anda method thereof to bond an MEA base material and a gas diffusion layerby ultrasonic wave vibration welding, and improve quality of bondingbetween the MEA base material and the gas diffusion layer, andproductivity.

A bonding device of a fuel cell part according to one form of thepresent disclosure bonds an upper gas diffusion layer and a lower gasdiffusion layer to upper and lower surfaces of an MEA base materialthrough an adhesive layer, while disposing the MEA base material betweenthe upper gas diffusion layer and the lower gas diffusion layer, andincludes: a lower die that supports the MEA base material, the upper gasdiffusion layer, and the lower gas diffusion layer to be bonded witheach other; an upper die installed in an upper side of the lower die;and an ultrasonic wave vibration source that is installed to be capableof moving in a vertical direction at opposite sides of the upper die,compressing the upper gas diffusion layer, and applying ultrasonic wavevibration energy to the adhesive layer;

In addition, in the bonding device of the fuel cell part according toone form of the present disclosure, the ultrasonic wave vibration sourcemay apply ultrasonic wave vibration energy to a plurality of adhesivelayers, each applied in the form of a spot, to edge portions of theupper gas diffusion layer and the lower gas diffusion layer, which facesub-gaskets of the MEA base material.

In addition, in the bonding device of the fuel cell part according toone form of the present disclosure, the adhesive layer may be applied inthe form of a spot to the edge portions of the upper gas diffusion layerand the lower gas diffusion layer, which face each other at oppositesides of the MEA base material, and

In addition, in the bonding device of the fuel cell part according toone form of the present disclosure, the ultrasonic wave vibration sourcemay compress a local region of the upper gas diffusion layer, whichcorresponds to the adhesive layer.

In addition, a bonding device of a fuel cell part according to one formof the present disclosure is provided with an MEA base material thatforms electrode layers at opposite sides of an electrolyte membrane andcovers edge portions of the electrolyte membrane and the electrodelayers through sub-gaskets, and an upper gas diffusion layer and a lowergas diffusion layer where adhesive layers are applied in the form ofspots to edge portions that face the sub-gaskets at opposite sides ofthe MEA base material, and bonds the upper gas diffusion layer and thelower gas diffusion layer to upper and lower surfaces of the MEA basematerial through the adhesive layers, and includes: i) a lower die wherevacuum suction holes are formed on an upper surface thereof; ii) anupper die provided in an upper side of the lower die; iii) a vacuumadsorption member where vacuum suction holes are formed on a lowersurface thereof, and provided to be vertically movable in the upper die;and iv) an ultrasonic wave vibration source that is vertically movablein opposite sides of the upper die, while disposing the vacuumadsorption member therebetween, and applies ultrasonic wave vibrationenergy to the adhesive layer while compressing a local region set in theupper gas diffusion layer, while disposing the MEA base material betweenthe upper gas diffusion layer and the lower gas diffusion layer on thelower die.

In addition, the bonding device of the fuel cell part according to oneform of the present disclosure may further include v) an air dampingunit that is provided at opposite sides of the lower die, dampens acompression force of the ultrasonic wave vibration source, and appliesthe compression force and a damping force to the ultrasonic wavevibration source side as an air pressure that reacts with the ultrasonicwave vibration energy.

In addition, in the bonding device of the fuel cell part according toone form of the present disclosure, the vacuum adsorption member mayvacuum-adsorb the upper gas diffusion layer through the vacuum suctionholes.

In addition, in the bonding device of the fuel cell part according toone form of the present disclosure, the lower die may vacuum-adsorb theupper gas diffusion layer and the lower gas diffusion layer through thevacuum suction holes.

In addition, in the bonding device of the fuel cell part according toone form of the present disclosure, the lower die may partition a GDLadsorption area where the upper gas diffusion layer and the lower gasdiffusion layer are vacuum-sucked through the vacuum suction holes, andan MEA adsorption area where an edge portion of the MEA base material isvacuum-sucked.

In addition, in the bonding device of the fuel cell part according toone form of the present disclosure, the vacuum adsorption member mayform the vacuum suction holes at a lower surface thereof, and may beprovided to be vertically movable by a driving source that is providedin the upper die and includes an actuating cylinder.

In addition, in the bonding device of the fuel cell part according toone form of the present disclosure, the upper gas diffusion layer andthe lower gas diffusion layer may be applied with the adhesive layers atedge portions, which face each other at opposite sides of the MEA basematerial.

In addition, in the bonding device of the fuel cell part according toone form of the present disclosure, the ultrasonic wave vibration sourcemay compress a local region of the upper gas diffusion layer, whichcorresponds to the adhesive layer.

In addition, in the bonding device of the fuel cell part according toone form of the present disclosure, the ultrasonic wave vibration sourcemay include: a moving member that is provided to be vertically movablethrough a driving source that includes an actuating cylinder at oppositesides of the upper die; a converter that is provided in the movingmember and converts an electrical signal to mechanical vibration energy;a booster that is connected with the converter and amplifies andattenuates mechanical vibration energy; and a horn member that isconnected with the booster and compresses a local region of the uppergas diffusion layer that corresponds to the adhesive layer.

In addition, in the bonding device of the fuel cell part according toone form of the present disclosure, the horn member may include a pairof compression ends that compress a local region of the upper gasdiffusion layer that corresponds to the adhesive layer.

In addition, in the bonding device of the fuel cell part according toone form of the present disclosure, the compression end may be formed toprotrude in a downward direction while having a predetermined width, anda corner portion of the compression end, which compresses the localregion of the upper gas diffusion layer, may be rounded.

In addition, in the bonding device of the fuel cell part according toone form of the present disclosure, the air damping unit may be providedas a pair at opposite sides of the lower die corresponding to the localregion of the upper gas diffusion layer.

In addition, in the bonding device of the fuel cell part according toone form of the present disclosure, the air damping unit may include: anair chamber provided in the lower die with an open upper end; a dampingplate that closes the upper end of the air chamber and is provided to bevertically movable; and an air supply that is connected with the airchamber and supplies air at a predetermined pressure to the air chamber.

In addition, in the bonding device of the fuel cell part according toone form of the present disclosure, the air damping unit may furtherinclude a displacement sensor that is provided in the air chamber,senses vertical displacement of the damping plate, and outputs adetection signal to a controller.

In addition, a method for bonding a fuel cell part according to one formof the present disclosure provides: an MEA base material that formselectrode layers on opposite sides of an electrolyte membrane and coversedge portions of the electrolyte membrane and the electrode layersthrough sub-gaskets, and an upper gas diffusion layer and a lower gasdiffusion layer, each applied with an adhesive layer in the form of aspot at edge portions that face the sub-gaskets at opposite sides of theMEA base material, and bonds the upper gas diffusion layer and the lowergas diffusion layer to upper and lower surfaces of the MEA base materialthrough the adhesive layer by using the bonding device. The methodincludes: (a) loading the upper gas diffusion layer on a predeterminedarea of a lower die, and vacuum-adsorbing the upper gas diffusion layer;(b) lowering a vacuum adsorption member of an upper die,vacuum-adsorbing the upper gas diffusion layer through the vacuumadsorption member, and raising the vacuum adsorption member; (c) loadingthe lower gas diffusion layer on a predetermined area of the lower die,vacuum-adsorbing the lower gas diffusion layer, and loading the MEA basematerial on the lower gas diffusion layer; (d) lowering the vacuumadsorption member, and loading the upper gas diffusion layer on the MEAbase material; and (e) moving an ultrasonic wave vibration source in adownward direction, compressing the predetermined local regions set atopposite sides of the upper gas diffusion layer through a horn member ofthe ultrasonic wave vibration source, and applying ultrasonic wavevibration energy to the adhesive layer through the horn member.

In addition, in the method for bonding the fuel cell part according toone form of the present disclosure, in (e), a compression force of thehorn member may be dampened through an air damping unit of the lowerdie, and a damping force may be applied to the horn member through adamping plate as air compression that reacts with ultrasonic wavevibration energy.

In addition, in the method for bonding the fuel cell part according toone form of the present disclosure, in (e), displacement of the dampingplate that vertically moves in an air chamber of the air damping unitmay be sensed, and a detection signal may be output to a controller.

In addition, in the method for bonding the fuel cell part according toone form of the present disclosure, in (e), the controller may controlpressure of air supplied to the air chamber according to the detectionsignal of the displacement sensor.

In addition, in the method for bonding the fuel cell part according toone form of the present disclosure, in (a), vacuum suction may beapplied to vacuum suction holes of the lower die.

In addition, in the method for bonding the fuel cell part according toone form of the present disclosure, in (b), vacuum-adsorption pressurewith respect to the vacuum suction holes of the lower die may beblocked.

In addition, in the method for bonding the fuel cell part according toone form of the present disclosure, in (c), vacuum-adsorption pressuremay be applied to the vacuum suction holes of the lower die, and thelower gas diffusion layer and the MEA base material may bevacuum-sucked.

In addition, in the method for bonding the fuel cell part according toone form of the present disclosure, in (d), vacuum-adsorption pressuremay be applied to vacuum suction holes of the vacuum adsorption member.

In addition, in the method for bonding the fuel cell part according toone form of the present disclosure, in (e), vacuum-adsorption pressurewith respect to the vacuum suction holes of the vacuum adsorption membermay be blocked, and vacuum-suction with respect to the vacuum suctionholes of the lower die may be blocked.

According to one forms of the present disclosure, the bonding timebetween the MEA base material and the gas diffusion layer can beshortened by bonding the MEA base material and the gas diffusion layerusing ultrasonic wave vibration welding, and deformation and damage ofthe gas diffusion layer can be reduced.

In addition, other effects which may be obtained or expected by oneforms of the present disclosure will be directly or implicitly disclosedin the detailed description of the forms of the present disclosure. Thatis, various effects expected according to one forms of the presentdisclosure will be disclosed in the detailed description below.

Further areas of applicability will become apparent from the descriptionprovided herein. It should be understood that the description andspecific examples are intended for purposes of illustration only and arenot intended to limit the scope of the present disclosure.

DRAWINGS

In order that the disclosure may be well understood, there will now bedescribed various forms thereof, given by way of example, referencebeing made to the accompanying drawings, in which:

FIG. 1 and FIG. 2 schematically illustrate one fuel cell part applied toone form of the present disclosure;

FIG. 3 schematically shows a bonding device of the fuel cell partaccording to one form of the present disclosure;

FIG. 4 is a perspective view of a lower die applied to the bondingdevice of the fuel cell part according to one form of the presentdisclosure;

FIG. 5 is a plan schematic diagram of the lower die applied to thebonding device of the fuel cell part according to one form of thepresent disclosure;

FIG. 6 is a perspective view of an upper die applied to the bondingdevice of the fuel cell part according to one form of the presentdisclosure;

FIG. 7 is a plan schematic diagram of the lower die applied to thebonding device of the fuel cell part according to one form of thepresent disclosure;

FIG. 8 is a perspective view of a horn member of an ultrasonic wavevibration source applied to the bonding device of the fuel cell partaccording to one form of the present disclosure;

FIG. 9 is a front schematic diagram of a horn member of the ultrasonicwave vibration source applied to the bonding device of the fuel cellpart according to one form of the present disclosure;

FIG. 10 shows an air damping unit applied to the bonding device of thefuel cell part according to one form of the present disclosure; and

FIG. 11 to FIG. 20 are provided to illustrate a bonding method of a fuelcell part according to one form of the present disclosure.

The drawings described herein are for illustration purposes only and arenot intended to limit the scope of the present disclosure in any way.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is notintended to limit the present disclosure, application, or uses. Itshould be understood that throughout the drawings, correspondingreference numerals indicate like or corresponding parts and features.

The present disclosure will be described more fully hereinafter withreference to the accompanying drawings, in which exemplary forms of thedisclosure are shown. As those skilled in the art would realize, thedescribed forms may be modified in various different ways, all withoutdeparting from the spirit or scope of the present disclosure.

The drawings and description are to be regarded as illustrative innature and not restrictive. Like reference numerals designate likeelements throughout the specification.

Further, since size and thickness of each component illustrated in thedrawings are arbitrarily represented for convenience in explanation, thepresent disclosure is not particularly limited to the illustrated sizeand thickness of each component, and the thickness is enlarged andillustrated in order to clearly express various parts and areas.

In the following description, dividing names of components into first,second, and the like is to divide the names because the names of thecomponents are the same, and an order thereof is not particularlylimited.

In addition, unless explicitly described to the contrary, the word“comprise” and variations such as “comprises” or “comprising” will beunderstood to imply the inclusion of stated elements but not theexclusion of any other elements.

Further, terms such as “ . . . unit”, “ . . . means”, “ . . . unit”, and“ . . . member” described in the specification mean a unit of acollective configuration to perform at least one function or operation.

FIG. 1 and FIG. 2 schematically illustrate a fuel cell part as anexample applied to one form of the present disclosure, and FIG. 3schematically illustrates a bonding device of a fuel cell part accordingto one form of the present disclosure.

Referring to FIG. 1 to FIG. 3, a bonding device 100 of a fuel cell partaccording to one form of the present disclosure may be applied to asystem that automatically and continuously manufactures parts of unitfuel cells that form a fuel cell stack.

For example, as a main part of a fuel cell, a fuel cell part 1 appliedto one form of the present disclosure may be defined as a part to whichgas diffusion layers (GDL) 5 and 7 are respectively bonded to oppositesides (top and bottom sides in the drawing) of a membrane-electrodeassembly (MEA) 3 (hereinafter, referred to as a MEA base material).

Hereinafter, referring to the drawings, the gas diffusion layer 5 bondedto the top side of the MEA base material 3 will be referred to as anupper gas diffusion layer, and the gas diffusion layer 7 bonded to thebottom side of the MEA base material 3 will be referred to as a lowergas diffusion layer.

The MEA base material 3 forms an anode electrode layer 4 b in one side(a top side in the drawing) of an electrolyte membrane 4 a, and forms acathode electrode layer 4 c in another side (a bottom side in thedrawing) of the electrolyte membrane 4 a.

In addition, the MEA base material 3 further includes a sub-gasket 4 dthat protects the electrode layers 4 b and 4 c and the electrolytemembrane 4 a, and assures assemblability of the fuel cell. Thesub-gasket 4 d may be formed of, for example, polyester polymers.

Such a sub-gasket 4 d covers edge portions of the electrolyte membrane 4a and the electrode layers 4 b and 4 c, and forms top and bottom openends that open the electrode layers 4 b and 4 c. The sub-gasket 4 d isbonded to the edge portions of the electrode layers 4 b and 4 c throughthe end portions of the top and bottom open ends, and is bonded to theedge portion of the electrolyte membrane 4 a while extending to theoutside.

Here, the above-stated upper gas diffusion layer 5 functions to diffusehydrogen gas to the anode electrode layer 4 b of the MEA base material 3while having electrical conductivity. In addition, the lower gasdiffusion layer 7 functions to diffuse air to the cathode electrodelayer 4 c of the MEA base material 3 while having electricalconductivity. For example, the upper gas diffusion layer 5 and the lowergas diffusion layer 7 may have a structure in which carbonized paper isbonded to a top side of a microporous layer (MPL).

The upper gas diffusion layer 5 and the lower gas diffusion layer 7 maybe respectively bonded to the top side and the bottom side of the MEAbase material 3 by the bonding device 100 of the fuel cell partaccording to one form of the present disclosure, disposing the MEA basematerial 3 therebetween.

Further, the upper gas diffusion layer 5 and the lower gas diffusionlayer 7 may be bonded to the edge portions of the top and bottom openends of the sub-gasket 4 d in the MEA base material 3 by the bondingdevice 100 of the fuel cell part according to one form of the presentdisclosure. That is, the upper gas diffusion layer 5 and the lower gasdiffusion layer 7 may be bonded to the edge portions of the top andbottom open ends of the sub-gaskets 4 d, which face the upper gasdiffusion layer 5 and the lower gas diffusion layer 7.

Further, adhesive layers 9 are formed in the edge portions of the uppergas diffusion layer 5 and the lower gas diffusion layer 7, which facethe sub-gaskets 4 d at opposite sides of the MEA base material 3, tobond the edge portions and the sub-gaskets 4 d by means of adhesion.

The adhesive layer 9 is provided as a known adhesive that is capable ofbeing softened and melted when heat is applied and cured when theapplied heat is blocked. This adhesive layer 9 is applied in the form ofspots on opposite edges of the upper gas diffusion layer 5 and the lowergas diffusion layer 7, which face each other, on opposite sides of theMEA base material 3 in one form of the present disclosure.

In this case, the spot form means that the adhesive layer 9 is notcontinuously applied to the upper gas diffusion layer 5 and the lowergas diffusion layer 7 at the opposite edge portions (edge portions inthe horizontal direction in the drawing) in a line form but is appliedto a given section (e.g., 5×20 mm).

Such an adhesive layer 9 can be applied as single spots on oppositeedges of the upper gas diffusion layer 5 and the lower gas diffusionlayer 7, which face each other, at opposite sides of the MEA basematerial 3 as in the drawing.

The bonding device 100 of the fuel cell part according to one form ofthe present disclosure bonds the upper gas diffusion layer 5 and thelower gas diffusion layer 7 to top and bottom sides of the MEA basematerial 3 through the adhesive layer 9, while disposing the MEA basematerial 3 between the upper gas diffusion layer 5 and the lower gasdiffusion layer 7.

Further, the bonding device 100 of the fuel cell part according to oneform of the present disclosure compresses the upper gas diffusion layer5 and the lower gas diffusion layer 7, while disposing the MEA basematerial 3 therebetween, softens and melts the adhesive layer 9 byapplying heat thereto, and bonds edge portions of the upper gasdiffusion layer 5 and the lower gas diffusion layer 7 to edge portionsof the top and bottom open ends of the sub-gaskets 4 d through theadhesive layers 9.

Such a bonding device 100 of the fuel cell part according to one form ofthe present disclosure is formed with a structure that can shortenbonding time of the upper gas diffusion layer 5 and the lower gasdiffusion layer 7 with respect to the MEA base material 3, and minimizedeformation and damage of the upper gas diffusion layer 5 and the lowergas diffusion layer 7 due to the pressure.

For this, the bonding device 100 of the fuel cell part according to oneform of the present disclosure includes a lower die 10, an upper die 20,a vacuum adsorption member 30, an ultrasonic wave vibration source 50,and an air damping unit 70.

In one form of the present disclosure, the lower die 10 is installed atthe floor of a working area. Here, the lower die 10 may be equipped withvarious additional components such as various brackets, support blocks,plates, housings, covers, collars, rods, and the like. Such a lower die10 supports the upper gas diffusion layer 5 and the lower gas diffusionlayer 7, and the MEA base material 3 disposed therebetween to be bonded.

FIG. 4 is a perspective view of a portion of the lower die applied tothe bonding device of the fuel cell part according to one form of thepresent disclosure.

Referring to FIG. 1 to FIG. 4, the lower die 10 in one form of thepresent disclosure includes vacuum suction holes 11 formed on a topsurface thereof for vacuum adsorption of the MEA base material 3, theupper gas diffusion layer 5, and the lower gas diffusion layer 7 byvacuum suction pressure.

The vacuum suction holes 11 may be applied with the vacuum suction by avacuum pump (not illustrated), and the vacuum suction may be blocked bya general valve.

The lower die 10 forms a lower mold plane. As shown in FIG. 5, the lowermole plane partitions a GDL adsorption area 13 where the upper gasdiffusion layer 5 and the lower gas diffusion layer 7 are vacuum-suckedthrough the vacuum suction holes 11, and an MEA adsorption area 15 whereedge sides of the sub-gaskets 4 d of the MEA base material 3 arevacuum-sucked.

Referring to FIG. 1 to FIG. 3, the upper die 20 is provided in an upperside of the lower die 10 in one form of the present disclosure. Here,the upper die 20 may be equipped with various additional components suchas various brackets, support blocks, plates, housings, covers, collars,rods, and the like. The upper die 20 is fixed to an upper side of thelower die 10 while having a predetermined gap therebetween.

FIG. 6 is a perspective view of the upper die applied to the bondingdevice of the fuel cell part according to one form of the presentdisclosure, and FIG. 7 is a top plan view of the upper die applied tothe bonding device of the fuel cell part according to one form of thepresent disclosure.

Referring to FIG. 6 and FIG. 7, together with FIG. 3, in one form of thepresent disclosure, the vacuum adsorption member 30 vacuum-adsorbs theupper gas diffusion layer 5 loaded on the GDL adsorption area 13 (referto FIG. 5) on the lower die 10.

The vacuum adsorption member 30 corresponds to the GDL adsorption area13 of the lower die 10, and is installed to be movable back and forthbetween the two sides of the upper die 20 in the up and down directions.Such a vacuum adsorption member 30 includes an adsorption plate 31.

The adsorption plate 31 forms vacuum suction holes 33 for adsorption ofthe upper gas diffusion layer 5 with vacuum suction. A vacuum suctionmay be applied to the vacuum suction holes 33 by a vacuum pump (notillustrated), and the vacuum suction may be blocked by a general valve.

Such a vacuum adsorption member 30 is installed to be capable ofreciprocating in a vertical direction by a first driving source 35provided on the upper die 20. For example, the first driving source 35includes a known actuating cylinder 37 operated by pneumatic orhydraulic pressure. An actuating rod 39 of the actuating cylinder 37 isconnected with the vacuum adsorption member 30.

Referring to FIG. 1 to FIG. 3, in one form of the present disclosure,the ultrasonic wave vibration source 50 applies ultrasonic wavevibration energy to the adhesive layer 9 while compressing apredetermined local region of the upper gas diffusion layer 5, whiledisposing the MEA base material 3 between the upper gas diffusion layer5 and the lower gas diffusion layer 7 on the lower die 10.

Further, the ultrasonic wave vibration source 50 may apply ultrasonicwave vibration energy to the adhesive layer 9 while compressing localregions of the upper gas diffusion layer 5, which respectivelycorrespond to the adhesive layers 9.

The ultrasonic wave vibration source 50 is disposed at opposite sides ofthe upper die 20, and thus ultrasonic wave vibration sources 50 can beinstalled to be capable of reciprocating in a vertical direction at theopposite sides of the upper die 20. The ultrasonic wave vibration source50 includes a moving member 51, a converter 52, a booster 53, and a hornmember 55.

The moving member 51 is installed to be capable of reciprocating in avertical direction through second driving sources 56 respectivelyprovided at opposite sides of the upper die 20. For example, the seconddriving source 56 includes a known actuating cylinder 57 operated bypneumatic or hydraulic pressure. An actuating rod 59 of the actuatingcylinder 57 is connected with the moving member 51.

The converter 52 (typically referred to as a vibrator in the art)converts an electrical signal to mechanical vibration energy, and isprovided in the moving member 51. In addition, the booster 53 amplifiesand attenuates mechanical vibration energy, and is connected with theconverter 52.

Since the configuration of the converter 52 and the booster 53 isadopted in a known ultrasonic wave vibrating apparatus that is wellknown in the art, a detailed description of the configuration will beomitted in this specification.

Then, the horn member 55 substantially compresses the local region ofthe upper gas diffusion layer 5 corresponding to the adhesive layer 9 inthe MEA material 3, the upper gas diffusion layer 5, and the lower gasdiffusion layer 7, which are loaded on the lower die 10. In addition,the horn member 55 may apply mechanical vibration energy to eachadhesive layer 9 through the local region of the upper gas diffusionlayer 5.

Since the horn member 55 is connected with the booster 53, as shown inFIG. 8 and FIG. 9, the horn member 55 includes a pair of compressionends 61 for pressing the local region of the upper gas diffusion layer 5corresponding to the adhesive layer 9.

The compression ends 61 are provided in pairs on each horn member 55corresponding to the opposite edge portions of the upper gas diffusionlayer 5 and the lower gas diffusion layer 7 on both sides of the MEAbase material 3.

The compression end 61 has a predetermined width and is formed toprotrude downward along an edge direction of the upper gas diffusionlayer 5. Here, at the compression end 61, a corner portion for pressingthe local region of the upper gas diffusion layer 5 is provided with around shape.

The edge of the compression end 61 is rounded in order to minimizematerial surface damage to the local region of the upper gas diffusionlayer 5.

On the other hand, the compression end 61 of the horn member 55compresses the local region of the upper gas diffusion layer 5 andapplies the ultrasonic wave vibration energy to the adhesive layer 9through the local region. Then, the adhesive layer 9 is softened andmelted by applying heat by ultrasonic wave vibration energy, so that theedge portions of the upper gas diffusion layer 5 and the lower gasdiffusion layer 7 can be bonded to the edge portions of the top andbottom open ends of the sub-gaskets 4 d.

Referring to FIG. 1 to FIG. 4, in one form of the present disclosure,the air damping unit 70 dampens the compressive force of the ultrasonicwave vibration source 50, and applies the damping force as air pressurefor reaction with the compression force and the ultrasonic wavevibration energy to the ultrasonic wave vibration source 50.

The air damping unit 70 is installed on both sides of the upper surfaceof the lower die 10 corresponding to the horn member 55 of theultrasonic wave vibration source 50. Further, the air damping unit 70 isprovided in pairs on each side of the lower die 10 corresponding to thelocal region of the upper gas diffusion layer 5.

As shown in FIG. 10, the air damping unit 70 includes an air chamber 71,a damping plate 73, an air supply 75, and a displacement sensor 77.

The air chamber 71 is provided with an open upper end on the uppersurface of the lower die 10. The damping plate 73 closes the upper endof the air chamber 71 and is installed to be able to flow in the up anddown direction. The air supply 75 is connected with the air chamber 71and can supply air of a predetermined pressure into the air chamber 71.

Here, the damping plate 73 may be provided so as to be able to close andseal the air chamber 71 and to flow in the up-and-down direction withoutbeing detached from the open end side of the air chamber 71. The airsupply 75 may include air compressors or air blowers of known art.

The displacement sensor 77 is installed inside the air chamber 71. Thedisplacement sensor 77 senses upward and downward displacement of thedamping plate 73 and outputs a detection signal to a controller 90.

The displacement sensor 77 may include a linear encoder known in theart. The linear encoder is a reflection-type optoelectronic detectorthat detects the amount of displacement using lattice gradations of aglass scale, a light-emitting element, and a light-receiving device, andconverts light intensity change into an electrical signal to output theamount of displacement. Alternatively, the above-described displacementsensor 77 may include a well-known electronically-induced encoder thatdetects the amount of displacement in an electronically induced manner.

Meanwhile, as a controller for controlling the overall operation of thedevice 100, the controller 90 can be implemented as at least one controlprocessor operating by a predetermined program, and in order to performthe contents according to one form of the present disclosure, it maycontain a series of instructions.

Here, the controller 90 applies an electrical control signal to the airsupply 75 according to the detection signal of the displacement sensor77, and can control the air pressure supplied to the air chamber 71.

Hereinafter, operation of the bonding device 100 of the fuel cell part,and a bonding method of the fuel cell part using the bonding device 100according to one form of the present disclosure will be described indetail with reference to the above-described drawings and accompanyingdrawings.

FIG. 11 to FIG. 20 are provided for description of a bonding method ofthe fuel cell part according to one form of the present disclosure.

Referring to FIG. 11, the damping plate 73 of the air damping unit 70 atthe lower die 10 forms the same plane as the top surface of the lowerdie 10 by air pressure supplied to the air chamber 71 through the airsupply 75 at a predetermined pressure.

The vacuum adsorption member 30 in the upper die 20 is in a raised stateby the backward movement of the first driving source 35 and the vacuumsuction is blocked for the vacuum suction holes 33 of the vacuumadsorption member 30.

Further, at the upper die 20, the horn member 55 of the ultrasonic wavevibration source 50 is raised with the converter 52 and booster 53through the moving member 51 in the backward motion of the seconddriving source 56.

In such a state, in one form of the present disclosure, the upper gasdiffusion layer 5 is loaded on a predetermined region on the uppersurface of the lower die 10, and the upper gas diffusion layer 5 isapplied with an adhesive layer 9 in the form of single spots at oppositeedge portions thereof.

Here, the loading of the upper gas diffusion layer 5 may be carried outby a robot gripper (not illustrated in the drawing). In one form of thepresent disclosure, the upper gas diffusion layer 5 is loaded on the GDLadsorption area 13 on the top side of the lower die 10.

Next, in one form of the present disclosure, the vacuum suction isapplied to the vacuum suction holes 11 of the lower die 10 through avacuum pump (not shown in the drawing). Then, the upper gas diffusionlayer 5 is vacuum-sucked in the GDL adsorption area 13 by the vacuumsuction acting on the vacuum suction holes 11 of the lower die 10, andis maintained in the correct position.

Next, in one form of the present disclosure, as shown in FIG. 12, thefirst driving source 35 lowers the vacuum adsorption member 30 andregulates the upper gas diffusion layer 5 on the lower die 10 throughthe vacuum adsorption member 30.

Then, in one form of the present disclosure, the vacuum suction actingon the vacuum suction holes 11 of the lower die 10 is blocked, and atthe same time, a vacuum suction is applied to the vacuum suction holes33 of the vacuum adsorption member 30 and the upper gas diffusion layer5 is vacuum-sucked to the vacuum adsorption member 30 by the vacuumsuction acting on the vacuum suction holes 33.

Next, in one form of the present disclosure, as shown in FIG. 13, thefirst driving source 35 causes the vacuum adsorption member 30 to rise.Then, the upper gas diffusion layer 5 is vacuum-sucked to the vacuumadsorption member 30, and moves in the upper direction.

Next, in one form of the present disclosure, as shown in FIG. 14, thelower gas diffusion layer 7 is loaded on a predetermined region on theupper surface of the lower die 10, and the lower gas diffusion layer 7is applied with an adhesive layer 9 in the form of single spots atopposite edge portions thereof.

Here, the loading of the lower gas diffusion layer 7 may be carried outby a robot gripper (not illustrated in the drawing). In one form of thepresent disclosure, the lower gas diffusion layer 7 is loaded on the GDLadsorption area 13 on the top side of the lower die 10.

Next, in one form of the present disclosure, the vacuum suction isapplied to the vacuum suction holes 11 of the lower die 10 through avacuum pump (not shown in the drawing). Then, the lower gas diffusionlayer 7 is vacuum-sucked in the GDL adsorption region 13 by the vacuumsuction acting on the vacuum suction holes 11 of the lower die 10, andis maintained in the correct position.

Then, as shown in FIG. 15, in one form of the present disclosure, theMEA base material 3 is loaded onto the lower gas diffusion layer 7 ofthe lower die 10 in a state that the vacuum adsorption member 30 movesupward while vacuum-adsorbing the upper gas diffusion layer 5. At thistime, loading of the MEA base material 3 can be carried out by a robotgripper not shown in the drawing.

In this process, since the vacuum suction acts on the vacuum suctionholes 11 of the lower die 10, the lower gas diffusion layer 7 isvacuum-sucked by the vacuum suction in the GDL adsorption area 13 and atthe same time the edge side of the sub-gasket 4 d of the MEA basematerial 3 is vacuum-sucked in the MEA adsorption area 15. Accordingly,the MEA base material 3 can be maintained at the right position on thelower gas diffusion layer 7.

Next, as shown in FIG. 16, in one form of the present disclosure, theupper gas diffusion layer 5 vacuum-sucked on the vacuum adsorptionmember 30 is loaded on the MEA base material 3, while the vacuumadsorption member 30 is lowered by the forward operation of the drivingsource 35.

The loading of the upper gas diffusion layer 5 means that the upper gasdiffusion layer 5 is placed on the MEA base material 3 by pressing theMEA base material 3 through the vacuum adsorption member 30.

In this case, the MEA base material 3 is located between the upper gasdiffusion layer 5 and the lower gas diffusion layer 7, and the adhesivelayers 9 of the upper gas diffusion layer 5 and the lower gas diffusionlayer 7 are located at the edge portions of the top and bottom open endsof the sub-gaskets 4 d of the MEA base material 3.

Next, as shown in FIG. 17, in one form of the present disclosure, whilevacuum suction with respect to the vacuum suction holes 33 of the vacuumadsorption member 30 is blocked, the moving member 51 of the ultrasonicwave vibration source 50 is lowered by the forward movement of thesecond driving source 56 and the horn member 55 is moved in the lowerdirection together with the converter 52 and the booster 53 through themoving member 51.

Then, the horn member 55 compresses the local region of the upper gasdiffusion layer 5 corresponding to the adhesive layer 9 to apredetermined pressure (for example, 250 to 450 N) through thecompression end 61. At this time, the local region of the upper gasdiffusion layer 5 is located on the damping plate 73 side of theabove-mentioned air damping unit 70.

As shown in FIG. 18, the damping plate 73 is moved in the lowerdirection by overcoming the predetermined air pressure (air pressure ofless than the pressure of the horn member) in the air chamber 71 by thepressure of the horn member 55, and dampens the compression force of thehorn member 55.

In this case, the displacement sensor 77 detects the displacement of thedamping plate 73 and outputs the detection signal to the controller 90.The controller 90 then applies an electrical signal to the air supply 75at a time when the displacement of the damping plate 73 sensed by thedisplacement sensor 77 satisfies a predetermined reference value, andair pressure corresponding to the pressing force of the horn member 55is supplied to the inside of the air chamber 71 through the air supply75.

In this case, the predetermined reference value means a displacementvalue of the damping plate 73 corresponding to a value obtained bysubtracting the thickness after the compression at the local region ofthe upper gas diffusion layer 5 and the lower gas diffusion layer 7 fromthe thickness before the compression at the local region.

For example, when the pre-compression thickness of the local region ofthe upper gas diffusion layer 5 and the lower gas diffusion layer 7 is600 μm, the local region may be compressed to a thickness of about500-540 μm by a compression force of the compression end 51 and adamping force of the compression region of the compression end 61.

In this case, in one form of the present disclosure, the corners of thecompression end 61 are formed in a round shape and thus the damage ofthe material surface to the local region of the upper gas diffusionlayer 5 can be reduced.

In such a state, in one form of the present disclosure, the vacuumsuction for the vacuum suction holes 11 of the lower die 10 is blockedand an electrical signal is applied to the converter 52 of theultrasonic wave vibration source 50.

Then, the electrical signal is converted into mechanical vibrationenergy through the converter 52, the mechanical vibration energy isamplified and attenuated by the booster 53, and a predeterminedamplitude (for example, 20 KHz/20-30 μm) is applied to the compressionend 61 of the horn member 55.

As shown in FIG. 19, the ultrasonic wave vibration energy is transmittedto the damping plate 73 through the compression end 61, and in one formof the present disclosure, the displacement of the damping plate 73,which moves up and down by the ultrasonic wave vibration energy, isdetected and a detection signal is output to the controller 90.

Thus, the controller 90 applies an electrical signal to the air supply75 according to the displacement of the damping plate 73, adjusts thepressure of the air acting on the air chamber 71 through the air supply75, and provides a damping force as an air pressure to the dam plate 73.

Accordingly, in one form of the present disclosure, ultrasonic wavevibration energy can be transmitted to the local region of the upper gasdiffusion layer 5, the adhesive layer 9 of the upper gas diffusion layer5, the MEA base material 3, the adhesive layer 9 of the lower gasdiffusion layer 7, and the local region of the lower gas diffusion layer7 through the compression force of the compression end 61 and thedamping force of the damping plate 73.

Thus, in one form of the present disclosure, the ultrasonic wavevibration energy is applied to the adhesive layer 9 to soften and meltthe adhesive layer 9 by the internal heating from the ultrasonic wavevibration energy, and the edge portions of the upper layer gas diffusionlayer 5 and the lower gas diffusion layer 7 can be bonded to the top andbottom open end edges of the sub-gaskets 4 d through the adhesive layers9.

Finally, in one form of the present disclosure, as shown in FIG. 20,when the vacuum adsorption member 30 is raised by the backward operationof the first driving source 35 and the horn member 55 of the ultrasonicwave vibration source 50 is raised by the backward operation of thesecond driving source 56, the fuel cell part 1 in which the upper gasdiffusion layer 5 and the lower gas diffusion layer 7 are bonded to theupper and lower surfaces of the MEA base material 3 can be manufactured.

Unlike the conventional hot press method, the bonding device 100 of thefuel cell part and the bonding method using the same according to theabove-described exemplary form of the present disclosure can bond thegas diffusion layers 5 and 7 to the upper and lower surfaces of the MEAbase material 3 in a manner of welding by softening and melting theadhesive layers 9 with heat applied thereto by ultrasonic wavevibration.

Therefore, in one form of the present disclosure, the ultrasonic wavevibration energy is applied to the adhesive layer 9 while compressingthe local region of the gas diffusion layers 5 and 7 at a relatively lowpressure (e.g., 60 kgf) compared to the hot press method, and thus theplastic deformation and damage of the outer material (carbonized paper)of the gas diffusion layers 5 and 7 can be reduced, and the bondingquality (durability etc.) of the gas diffusion layers 5 and 7 can beimproved.

In addition, in one form of the present disclosure, since thecompression force and the ultrasonic wave vibration energy of theultrasonic wave vibration source 50 can be buffered through the airdamping unit 70, the local regions of the upper gas diffusion layer 5and the lower gas diffusion layer 7, which are brittle, can be inhibitedfrom being damaged.

In one form of the present disclosure, the ultrasonic wave vibrationsource 50 compresses the local regions of the gas diffusion layers 5 and7 and applies the ultrasonic wave vibration energy to the adhesivelayers 9. Therefore, compared to the hot press method, productivity ofthe fuel cell part 1 can be further improved, for example, by shorteningthe bonding cycle time (for example, 5 seconds) between the MEA basematerial 3 and the gas diffusion layers 5 and 7.

In one form of the present disclosure, unlike the conventional hot-pressmethod in which heat is directly applied to the adhesive layer throughthe gas diffusion layer and the MEA base material, a method in whichheat is locally applied to the adhesive layer 9 through ultrasonic wavevibration energy is adopted, and thus it is possible to inhibit theelectrolyte membrane of the MEA base material 3 from being thermallydeformed.

Furthermore, in one form of the present disclosure, a method of weldingthe MEA material 3 and the gas diffusion layers 5 and 7 by ultrasonicwave vibration energy while applying adhesive layer 9 in a spot form togas diffusion layers 5 and 7 is employed, and thus consumption of theadhesive and the cost of the adhesive can be reduced.

Hereinabove, although exemplary forms of the present disclosure aredescribed, the spirit of the present disclosure is not limited to theforms set forth herein and those skilled in the art and understandingthe present disclosure can easily accomplish other forms included in thespirit of the present disclosure by the addition, modification, andremoval of components within the same spirit, but those are construed asbeing included in the spirit of the present disclosure.

While this present disclosure has been described in connection with whatis presently considered to be practical exemplary forms, it is to beunderstood that the present disclosure is not limited to the disclosedforms, but, on the contrary, it is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the present disclosure.

<Description of symbols>  1 . . . fuel cell part  3 . . . MEA basematerial  4a: electrolyte membrane  4b: anode electrode layer  4c:cathode electrode layer  4d: sub-gasket  5: upper gas diffusion layer 7: lower gas diffusion layer  9: adhesive layer 10: lower die 11, 33:vacuum suction holes 13: GDL adsorption area  15: MEA adsorption area20: upper die  30: vacuum adsorption member 31: adsorption plate  35:first driving source 37, 57: actuating cylinder 39, 59: actuating rod50: ultrasonic wave vibration source  51: moving member 52: converter 53: booster 55: horn member  56: second driving source 61: compressionend  70: air damping unit 71: air chamber  73: damping plate 75: airsupply  77: displacement sensor 90: controller 100: bonding device

What is claimed is:
 1. A bonding device of a fuel cell part, which bondsan upper gas diffusion layer and a lower gas diffusion layer to upperand lower surfaces of a membrane-electrode assembly (MEA) base materialthrough an adhesive layer, while disposing the MEA base material betweenthe upper gas diffusion layer and the lower gas diffusion layer,comprising: a lower die that supports the MEA base material, the uppergas diffusion layer, and the lower gas diffusion layer to be bonded witheach other; an upper die installed in an upper side of the lower die;and an ultrasonic wave vibration source that is configured to move in avertical direction at opposite sides of the upper die, compress theupper gas diffusion layer, and apply ultrasonic wave vibration energy tothe adhesive layer.
 2. The bonding device of claim 1, wherein theultrasonic wave vibration source applies ultrasonic wave vibrationenergy to a plurality of adhesive layers, each applied as a spot, atedge portions of the upper gas diffusion layer and the lower gasdiffusion layer, which face sub-gaskets of the MEA base material.
 3. Thebonding device of claim 2, wherein the adhesive layer is applied as aspot to the edge portions of the upper gas diffusion layer and the lowergas diffusion layer, which face each other at opposite sides of the MEAbase material, and the ultrasonic wave vibration source compresses alocal region of the upper gas diffusion layer, which corresponds to theadhesive layer.
 4. A bonding device of a fuel cell part comprising: anMEA base material that forms electrode layers at opposite sides of anelectrolyte membrane and covers edge portions of the electrolytemembrane and the electrode layers through sub-gaskets; an upper gasdiffusion layer and a lower gas diffusion layer; adhesive layers appliedas spots to edge portions that face the sub-gaskets at opposite sides ofthe MEA base material, the adhesive layers bonding the upper gasdiffusion layer and the lower gas diffusion layer to upper and lowersurfaces of the MEA base material through the adhesive layers; a lowerdie where vacuum suction holes are formed on an upper surface thereof;an upper die provided in an upper side of the lower die; a vacuumadsorption member where vacuum suction holes are formed on a lowersurface thereof, and provided to be vertically movable in the upper die;and an ultrasonic wave vibration source that is vertically movable inopposite sides of the upper die, while disposing the vacuum adsorptionmember therebetween, and applies ultrasonic wave vibration energy to theadhesive layer while compressing a local region set in the upper gasdiffusion layer, while disposing the MEA base material between the uppergas diffusion layer and the lower gas diffusion layer on the lower die.5. The bonding device of claim 4, further comprising an air damping unitthat is provided at opposite sides of the lower die, which air dampingunit dampens a compression force of the ultrasonic wave vibrationsource, and applies the compression force and a damping force to a sideof the lower die processed by the ultrasonic wave vibration source as anair pressure that reacts with the ultrasonic wave vibration energy. 6.The bonding device of claim 4, wherein the vacuum adsorption membervacuum-adsorbs the upper gas diffusion layer through the vacuum suctionholes, and the lower die vacuum-adsorbs the upper gas diffusion layerand the lower gas diffusion layer through the vacuum suction holes. 7.The bonding device of claim 4, wherein the lower die partitions a gasdiffusion layer adsorption area where the upper gas diffusion layer andthe lower gas diffusion layer are vacuum-sucked through the vacuumsuction holes, and an MEA adsorption area where an edge portion of theMEA base material is vacuum-sucked.
 8. The bonding device of claim 4,wherein the vacuum adsorption member forms the vacuum suction holes at alower surface thereof, and is provided to be vertically movable by adriving source that is provided in the upper die and includes anactuating cylinder.
 9. The bonding device of claim 4, wherein the uppergas diffusion layer and the lower gas diffusion layer are applied withthe adhesive layers at edge portions, which face each other at oppositesides of the MEA base material, and the ultrasonic wave vibration sourcecompresses a local region of the upper gas diffusion layer, whichcorresponds to the adhesive layer.
 10. The bonding device of claim 4,wherein the ultrasonic wave vibration source comprises: a moving memberthat is provided to be vertically movable through a driving source thatincludes an actuating cylinder at opposite sides of the upper die; aconverter that is provided in the moving member and converts anelectrical signal to mechanical vibration energy; a booster that isconnected with the converter and amplifies and attenuates mechanicalvibration energy; and a horn member that is connected with the boosterand compresses a local region of the upper gas diffusion layer thatcorresponds to the adhesive layer.
 11. The bonding device of claim 10,wherein the upper gas diffusion layer and the lower gas diffusion layerare applied with the adhesive layers at edge portions which face eachother at opposite sides of the MEA base material, and the horn membercomprises first compression end and a second compression end, thecompression ends compressing a local region of the upper gas diffusionlayer that corresponds to the adhesive layer.
 12. The bonding device ofclaim 11, wherein the first compression end is formed to protrude in adownward direction while having a predetermined width, and a cornerportion of the compression end, which compresses the local region of theupper gas diffusion layer, is rounded.
 13. The bonding device of claim5, wherein the air damping unit is provided as a pair at opposite sidesof the lower die corresponding to the local region of the upper gasdiffusion layer.
 14. The bonding device of claim 5, wherein the airdamping unit comprises: an air chamber provided in the lower die with anopen upper end; a damping plate that closes the upper end of the airchamber and is provided to be vertically movable; and an air supply thatis connected with the air chamber and supplies air at a predeterminedpressure to the air chamber.
 15. The bonding device of claim 14, whereinthe air damping unit further comprises a displacement sensor that isprovided in the air chamber, senses vertical displacement of the dampingplate, and outputs a detection signal to a controller.